When you're talking about Bristol Bay, you're talking about the greatest wild salmon system left on the planet.

This would be cultural genocide to our people. We would not be able to live here.

Salmon and clean water are the heartbeat of this region.

Does the mine threaten the fisheries? Not at all. Not at all. are the heartbeat of this region.

Does the mine threaten the fisheries?

Not at all.

Not at all.

No. Even winter's starkness can't diminish Alaska's vast natural wonders.

Waters the team with fish lap against land rich with minerals.

Wonders on a slow motion collision course with a proposed gold and copper mine

at the headwaters of the world's largest salmon run.

I'm Ann Thompson, and this is NBC on Earth.

If you eat wild salmon, it was likely caught here in Bristol Bay, Alaska.

A marine ecosystem comprised of not just the ocean,

but freshwater lakes and streams home to tens of millions of salmon.

So what's the controversy?

A mining company called the Pebble Limited Partnership

wants to build a gold and copper mine

many worry could poison the waters.

Tim Bristol and the executive director of Salmon State, based here in Alaska.

Salmon State is a conservation advocacy organization.

What is the connection that Alaskans have with the land in the water?

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